Class System of sencha is the strongest features for developers. We can easily see the influence of other languages in Sencha Touch's Class System, which powers this heavily object-oriented framework. The internal, as well as the front facing, parts are well abstracted and defined to make it easy to extend and build on top of any component of an inheritance chain.
Sench Touch class system handling dependencies in Ext.Loader in development or Sencha Cmd builder for Production builds where and how to find them. Comparing other tools, Sencha Touch Class System applies nice structured app development.